Hey DSL, check this out:

http://www.rclipos.com/Accessories.htm

If you scroll down you'll see the ThunderPower adapters. I'm giong to post some questions in another thread (8th scale conversions) about this to see what anybody else says.

These adapters look a little hack, and you can see that they simply eliminate the last wire, so I don't know if this is a good solution or not.

By the way: your title to this thread is a little vague and may be why nobody had replied. Can you change the title so something like "ThunderPower 4S Balancing Adapter Help" ? That might get more responses.